PS/2 Keyboard for Apple II

Why?

I was cleaning up my cellar the other day as I found my old Apple II europlus.
Since it was the computer I’ve started programming on (not in the 70s, though) I’m a little emotionally attached to that old beast and decided to toy around with it a bit – AFTER cleaning up the cellar of course ;).

Unfortunately most of the keys hardly worked, quite some were completely broken – the age (around 30 years) definitely shows.
I tried to fix the keys a few years ago but gave up, since they kept breaking at an incredible rate.

Thus I decided to build a converter that enables me to use a common (and much more comfortable) PC-keyboard.

This is what you’ll need

A 6-pin Mini-DIN female (jack) – I unsoldered mine from an old motherboard

A proper amount of nostalgia

Building it

The pin-assignments of the PIC seem a little random, especially the Dx-lines. However, like this it’s possible to piggy-back the PIC (14 pins) on top of the keyboard-socket (16 pins) on the motherboard.
It’s not hard to figure out how, here are a few tips:

Even if it’s obvious: don’t solder everything directly to the keyboard-socket, put another 16-pin IC-socket with pins on both sides inbetween

Piggy-back in a way so pin 1 of the keyboard-socket and pin 1 of the PIC line up

GND is at pin 8 of the keyboard-socket – you need to connect it to the PIC’s pin 14